From: Roland Scheidegger <[EMAIL PROTECTED]> The i8042 driver fails detection of the AUX port with some chips, because they apparently do not change the I8042_CTR_AUXDIS bit immediately. This is known to affect at least HP500 / HP510 notebooks, consequently the built-in touchpad will not work. The patch will simply reread the value until it gets the expected value or a retry limit is hit, without touching other workaround code in the same area.
Signed-off-by: Roland Scheidegger <[EMAIL PROTECTED]> --- There is some discussion about non-working touchpads in HP500 notebooks in ubuntu and a (ugly) workaround for this problem here: http://ubuntuforums.org/showthread.php?t=344103. I've got a HP510 and even with 2.6.21 the aux port would get disabled. Works with the patch, for the record the i8042 here needs around 6 tries (sometimes a bit more, sometimes less) until it reads the I8042_CTR_AUXDIS bit correctly, both after disabling and enabling the aux port. (please CC: on any replies) Signed-off-by: Roland Scheidegger <[EMAIL PROTECTED]> --- linux-2.6/drivers/input/serio/i8042.c.orig 2007-05-03 16:32:26.000000000 +0200 +++ linux-2.6/drivers/input/serio/i8042.c 2007-05-03 16:56:00.000000000 +0200 @@ -537,6 +537,7 @@ static int __devinit i8042_check_aux(voi int retval = -1; int irq_registered = 0; int aux_loop_broken = 0; + int i = 0; unsigned long flags; unsigned char param; @@ -582,14 +583,27 @@ static int __devinit i8042_check_aux(voi if (i8042_command(¶m, I8042_CMD_AUX_DISABLE)) return -1; - if (i8042_command(¶m, I8042_CMD_CTL_RCTR) || (~param & I8042_CTR_AUXDIS)) { + /* some chips need some time to set the I8042_CTR_AUXDIS bit */ + for (i = 0; i < 100; i++) { + if (!i8042_command(¶m, I8042_CMD_CTL_RCTR) && (param & I8042_CTR_AUXDIS)) + break; + udelay(50); + } + if (i == 100) { printk(KERN_WARNING "Failed to disable AUX port, but continuing anyway... Is this a SiS?\n"); printk(KERN_WARNING "If AUX port is really absent please use the 'i8042.noaux' option.\n"); } if (i8042_command(¶m, I8042_CMD_AUX_ENABLE)) return -1; - if (i8042_command(¶m, I8042_CMD_CTL_RCTR) || (param & I8042_CTR_AUXDIS)) + for (i = 0; i < 100; i++) { + if (i8042_command(¶m, I8042_CMD_CTL_RCTR)) + return -1; + if (~param & I8042_CTR_AUXDIS) + break; + udelay(50); + } + if (i == 100) return -1; /* - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
